When a TLS-capable server negotiates SSL 2.0 it SHOULD, after
decrypting the ENCRYPTED-KEY-DATA field, check that these 8 padding
bytes are 0x03. If they are not, the server SHOULD generate a random
value for SECRET-KEY-DATA, and continue the handshake (which will
eventually fail since the keys will not match).

It should say:

When a TLS-capable server negotiates SSL 2.0 it SHOULD, after
decrypting the ENCRYPTED-KEY-DATA field, check that these 8 padding
bytes are not all 0x03. If they are, the server SHOULD generate a random
value for SECRET-KEY-DATA, and continue the handshake (which will
eventually fail since the keys will not match).

Notes:

The condition is the wrong way around. When the bytes *are* all 0x03, that means the client supports TLS, so there must have been a version rollback attack in order for SSL 2.0 to be negotiated. For example, see the NSS implementation (line number may rot):

The supported_signature_algorithms field is a variable length array. As such ceiling and floor should be specified, and they should be multiple of the base type (which is two bytes long in this case). See section 7.4.1.4.1 for a valid definition of this field.

The appendix definition of ASN.1Cert leaves out the floor of the variable-length vector, which must be specified according to the vector syntax specification in section 4.3. Fortunately, the original definition of ASN.1Cert in section 7.4.2 does specify the floor as 1, so the definition in A.4.2 should be updated to match.

In the following example, Datum is defined to be three consecutive
bytes that the protocol does not interpret, while Data is three
consecutive Datum, consuming a total of nine bytes.
opaque Datum[3]; /* three uninterpreted bytes */
Datum Data[9]; /* 3 consecutive 3 byte vectors */

It should say:

In the following example, Datum is defined to be three consecutive
bytes that the protocol does not interpret, while Data is three
consecutive Datum, consuming a total of nine bytes.
opaque Datum[3]; /* three uninterpreted bytes */
Datum Data[3]; /* 3 consecutive 3 byte vectors */

Notes:

The 9 in "Datum Data[9]" should be a 3 because Datum is a data type that consumes 3 bytes, so as written the Data vector is 27 bytes long. To make it a 9 byte vector the 9 must change to a 3.

Note: To help avoid pipeline stalls, ChangeCipherSpec is an
independent TLS protocol content type, and is not actually a TLS
handshake message.

It should say:

Note: To avoid ChangeCipherSpec being transmitted in mix with
other handshake fragments in one record, ChangeCipherSpec is
an independent TLS protocol content type, and is not actually
a TLS handshake message. To help avoid pipeline stalls,
ChangeCipherSpec is sent from both the server and the client.

Notes:

The original text can be read like we can handle ChangeCipherSpec asynchronously.
This is harmful and may be a cause of CCS Injection vulnerability.

The additional authenticated data, which we denote as
additional_data, is defined as follows:
additional_data = seq_num + TLSCompressed.type +
TLSCompressed.version + TLSCompressed.length;
where "+" denotes concatenation.
The aead_output consists of the ciphertext output by the AEAD
encryption operation. The length will generally be larger than
TLSCompressed.length, but by an amount that varies with the AEAD
cipher. Since the ciphers might incorporate padding, the amount of
overhead could vary with different TLSCompressed.length values. Each
AEAD cipher MUST NOT produce an expansion of greater than 1024 bytes.
Symbolically,

It should say:

The additional authenticated data, which we denote as
additional_data, is defined as follows:
additional_data = seq_num + TLSCompressed.type +
TLSCompressed.version + TLSCompressed.length;
where "+" denotes concatenation.
The aead_output consists of the ciphertext output by the AEAD
encryption operation. The length will generally be larger than
TLSCompressed.length, but by an amount that varies with the AEAD
cipher. Each AEAD cipher MUST NOT produce an expansion of greater
than 1024 bytes. Symbolically,

Notes:

I suggest leaving the sentence about padding out. The value for TLSCompressed.length is required by additional_data for both encryption and decryption. Therefore, it must be possible to determine the TLSCompressed.length from the ciphertext before decryption.

In practice this is done by subtracting the integrity check value length from the ciphertext length, where the integrity check value length is defined by each AEAD cipher separately. If the cipher incorporates variable padding, it is impossible to calculate the TLSCompressed.length without an explicit value sent for each ciphertext separately. Therefore to avoid confusion, it would be better not to mention anything about padding at all.

(issue discussed on tls@ietf.org and with Eric Rescorla, result of both discussions was that padding in AEAD ciphers doesn't seem to be possible with the current specification)

Example: If the block length is 8 bytes, the content length
(TLSCompressed.length) is 61 bytes, and the MAC length is 20 bytes,
then the length before padding is 82 bytes (this does not include the
Dierks & Rescorla Standards Track [Page 23]
RFC 5246 TLS August 2008
IV. Thus, the padding length modulo 8 must be equal to 6 in order to
make the total length an even multiple of 8 bytes (the block length).
The padding length can be 6, 14, 22, and so on, through 254. If the
padding length were the minimum necessary, 6, the padding would be 6
bytes, each containing the value 6. Thus, the last 8 octets of the
GenericBlockCipher before block encryption would be xx 06 06 06 06 06
06 06, where xx is the last octet of the MAC.

It should say:

Example: If the block length is 8 bytes, the content length
(TLSCompressed.length) is 61 bytes, and the MAC length is 20 bytes,
then the length before padding is 82 bytes (this does not include the
Dierks & Rescorla Standards Track [Page 23]
RFC 5246 TLS August 2008
IV). Thus, the padding length modulo 8 must be equal to 6 in order to
make the total length an even multiple of 8 bytes (the block length).
The padding length can be 6, 14, 22, and so on, through 254. If the
padding length were the minimum necessary, 6, the padding would be 6
bytes, each containing the value 6. Thus, the last 8 octets of the
GenericBlockCipher before block encryption would be xx 06 06 06 06 06
06 06, where xx is the last octet of the MAC.

"Obsoletes: 4366" is factually incorrect, because it is impossible to implement TLSv1.1 (rfc4346) or TLSv1.0(rfc2246) from the TLSv1.2 spec alone. (IPv6 does not obsolete IPv4 and HTTP/1.1 does not obsolete HTTP/1.0 either).

"Obsoletes: 4366" is factually incorrect, because some of the TLS extensions defined in rfc4366 do NOT appear in rfc5246 (and were updated by rfc6066). On top of that, in order to implement TLS extensions for TLSv1.0 or TLSv1.1, rfc4366 is indispensible, because it describes the necessary changes to the TLSv1.0 & TLSv1.1 PDUs, information that would be cumbersome to extract from rfc5246 compared to simply using rfc4366.

"Obsoletes: 3268" is factually incorrect, because 3268 is the document needed to implement the AES ciphersuites in implementations of TLS _prior_ to TLSv1.2,
such as TLSv1.0(rfc2246) and TLSv1.1(rfc4346), i.e. to add support for AES ciphersuites to an existing implementation of TLSv1.0, one would use TLSv1.0(rfc2246) plus rfc3268, rather than TLSv1.0 plus some undefined fragments of rfc5246.
--VERIFIER NOTES--
If you're looking to implement TLS 1.1 or TLS 1.0 you should be looking in those earlier specifications not RFC 5246.